1. Field of the Invention
The present invention relates to a wireless communication device, a MAC address management system, a wireless communication method, and a computer program and, more particularly, to a wireless communication device, a MAC address management system, a wireless communication method, and a computer program that perform wireless communication by using a temporary MAC address which can be temporarily used.
2. Description of the Related Art
A conventional wireless LAN card (100), as shown in FIG. 8, includes a wireless LAN control unit (101), an RF (Radio Frequency) control unit (102) and a ROM (Read Only Memory) (103).
The wireless LAN control unit (101) is to control various functions in the wireless LAN card (100): the unit 101 performs interface control for a wireless communication device such as a PC on which the wireless LAN card (100) is loaded to perform wireless communication, and performs wireless communication by using a unique MAC address stored in the ROM (103). The RF control unit (102) is to control wireless communication with an external device. The ROM (103) is to store a unique MAC address that is an identification number unique to each wireless LAN card allocated when a card was manufactured.
Since the wireless LAN card (100) shown in FIG. 8 performs wireless communication by using the unique MAC address stored in the ROM (103), once radio waves of the wireless communication are intercepted, the unique MAC address may be revealed from the intercepted radio waves. Consequently, an interceptor of the MAC address could specify a user of the wireless LAN card (100) on the basis of the unique MAC address, and monitor a behavior of the user who uses the wireless LAN card (100). In this case, the privacy of the user who uses the wireless LAN card (100) cannot be protected.
In order to solve the above problem, for example, as shown in FIG. 9, a temporary MAC address that can be temporarily used is written in a flash memory 104, and the written temporary MAC address is used to perform wireless communication. In this way, the wireless communication can be performed without using the unique MAC address stored in the ROM (103) whereby the privacy of a user of the wireless LAN card (100) can be protected.
In this case, however, temporary MAC addresses can be sequentially updated so that when wireless communication is performed with the updated temporary MAC addresses, uniqueness of temporary MAC address cannot be maintained. There is also a danger that a false temporary MAC address will be written in the flash memory (104). Therefore, when the temporary MAC address is designed to be written in the flash memory (104) as shown in FIG. 9, another problem arises that there will be interference on wireless communication.
For this reason, wireless communication is desired to be performed by using a temporary MAC address different from a unique MAC address stored in the ROM (103) to protect the privacy of a user, and the uniqueness of temporary MAC address is maintained, so that interference is prevented on wireless communication.
As related art documents, Patent document 1 (Japanese Patent Application Laid-Open No. 2004-40806) discloses a wireless LAN system that secures the anonymity of a user. The wireless LAN system comprises (a) a wireless connection node that generates at least one temporary address set in correspondence with a MAC address of each wireless terminal, and uses as a target address a temporary address selected from the temporary address set, and (b) at least one wireless terminal that receives a temporary address set that was generated at the wireless connection node and corresponded to its own MAC address, and uses as a source address a temporary address selected from the received temporary address set.
Patent document 2 (Japanese Patent Application Laid-Open No. 2000-138692) discloses a MAC address management device that infallibly and safely gives a MAC address to a network interface device. In the system of Patent document 2, a network interface device forwards a supply request of MAC address information to a MAC address database server; the MAC address database server reads out a MAC address from a MAC address file and transmits the MAC address to the network interface device; the network interface device writes the MAC address in a built-in memory.
Though in Patent document 1 a wireless terminal receives a temporary address set generated at a wireless connection node, and a temporary address selected from the temporary address set is used as a source address, Patent document 1 does not disclose that code data which is an encoded temporary MAC address is obtained from a server device and then decoded for wireless communication.
In Patent document 2 the MAC address database server transmits a MAC address to the network interface device and writes the MAC address in the built-in memory. However, Patent document 2 does not disclose that code data, which is an encoded temporary MAC address, is obtained from a server device and then decoded for wireless communication.